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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
3
|
| pubmed:dateCreated |
1987-1-15
|
| pubmed:abstractText |
A homogeneous glutamate decarboxylase isolated from pig brain contains 0.8 mol of tightly bound pyridoxal 5-phosphate/enzyme dimer. Upon addition of exogenous pyridoxal 5-phosphate (pyridoxal-5-P), the enzyme acquires maximum catalytic activity. Preincubation of the enzyme with L-glutamate (10 mM) brings about changes in the absorption spectrum of bound pyridoxal-5-P with the concomitant formation of succinic semialdehyde. However, the rate of this slow secondary reaction, i.e. decarboxylative transamination, is 10(-4) times the rate of normal decarboxylation. It is postulated that under physiological conditions enzymatically inactive species of glutamate decarboxylase, generated by the process of decarboxylative transamination, are reconstituted by pyridoxal-5-P produced by the cytosolic enzymes pyridoxal kinase and pyridoxine-5-P oxidase. The catalytic activity of resolved glutamate decarboxylase is recovered by preincubation with phospho-pyridoxyl-ethanolamine phosphate. The experimental evidence is consistent with the interpretation that the resolved enzyme binds the P-pyridoxyl analog, reduces the stability of the covalent bond of the phospho-pyridoxyl moiety, and catalyzes the formation of pyridoxal-5-P.
|
| pubmed:grant | |
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:month |
Nov
|
| pubmed:issn |
0014-2956
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:day |
3
|
| pubmed:volume |
160
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
515-20
|
| pubmed:dateRevised |
2007-11-14
|
| pubmed:meshHeading | |
| pubmed:year |
1986
|
| pubmed:articleTitle |
Glutamate decarboxylase side reactions catalyzed by the enzyme.
|
| pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.,
Research Support, U.S. Gov't, Non-P.H.S.,
Research Support, Non-U.S. Gov't
|